WO2018003167A1

WO2018003167A1 - Method for producing silicon monocrystal

Info

Publication number: WO2018003167A1
Application number: PCT/JP2017/006782
Authority: WO
Inventors: 康裕齋藤; 最勝寺　俊昭; 一美田邉
Original assignee: 株式会社Sumco
Priority date: 2016-06-28
Filing date: 2017-02-23
Publication date: 2018-01-04
Also published as: JP2018002496A; KR20180124975A; JP6680108B2; KR102157389B1; TWI635199B; TW201800626A; CN109415843A; DE112017003224B4; CN109415843B; DE112017003224T5

Abstract

According to the present invention, correlations between a diameter (D) of a monocrystal (C) when being pulled up by a CZ process, a horizontal magnetic field strength (G) to be applied to a melt (M), a crystal rotation speed (V) of the monocrystal (C) being pulled up, and an oxygen concentration distribution characteristic (δ) at an outer periphery of a wafer are determined in advance for a prescribed production condition. Then, a minimum diameter of the monocrystal to be pulled up is determined on the basis of a limit value of the oxygen concentration distribution characteristic at the outer periphery of the wafer, a limit value of the horizontal magnetic field strength, a limit value of the crystal rotation speed of the monocrystal being pulled up, and the determined correlations. A silicon monocrystal is produced under the prescribed production condition using the determined minimum diameter as a target diameter.

Description

Method for producing silicon single crystal

The present invention relates to a method for producing a silicon single crystal.

In the horizontal magnetic field application Czochralski method (HMCZ method), convection is likely to occur at the surface of the melt in the crucible and convection is suppressed at the bottom of the crucible, so that the oxygen concentration distribution in the crystal growth axis direction is made uniform. It has been proposed (Patent Document 1).

JP-A-9-188590

By the way, the oxygen concentration in the range within about 10 mm from the outer peripheral edge of the wafer (hereinafter also referred to as the outer peripheral portion) is lower than the other central portions. Since such an outer peripheral portion can cause defects in the device process, in order to increase the device yield, it is required to make the oxygen concentration uniform up to the outer peripheral portion.

The problem to be solved by the present invention is to provide a method for producing a silicon single crystal capable of making the oxygen concentration in the wafer surface uniform up to the outer peripheral portion while minimizing the production cost of the silicon single crystal. .

In the invention according to the first aspect, the correlation between the diameter of the single crystal to be pulled up, the horizontal magnetic field strength, the crystal rotation of the single crystal, and the distribution characteristics of the oxygen concentration at the outer periphery of the wafer is obtained in advance for predetermined manufacturing conditions. The diameter of the single crystal to be pulled is determined from the correlation between the distribution characteristics of the oxygen concentration at the outer periphery of the wafer, the limit value of the horizontal magnetic field strength and the limit value of the crystal rotation of the single crystal, and the correlation. The above problem is solved by manufacturing a single crystal having a diameter under the predetermined manufacturing conditions.

In the invention according to the second aspect, the correlation between the diameter of the pulled single crystal, the horizontal magnetic field strength, the crystal rotation of the single crystal, and the distribution characteristics of the oxygen concentration in the outer periphery of the wafer is obtained in advance for predetermined manufacturing conditions. The horizontal magnetic field strength to be applied is determined from the distribution characteristics of the allowable oxygen concentration at the outer periphery of the wafer, the limit value of the diameter of the single crystal to be pulled up, the limit value of the crystal rotation of the single crystal, and the above correlation. The above problem is solved by manufacturing a single crystal under the determined horizontal magnetic field strength and the predetermined manufacturing conditions.

In the invention according to the third aspect, the correlation between the diameter of the pulled single crystal, the horizontal magnetic field strength, the crystal rotation of the single crystal, and the distribution characteristics of the oxygen concentration in the outer periphery of the wafer is obtained in advance for a predetermined manufacturing condition. The crystal rotation of the single crystal is obtained from the distribution characteristics of the oxygen concentration in the permissible outer periphery of the wafer, the limit value of the single crystal to be pulled up, the limit value of the horizontal magnetic field strength, and the correlation, and the calculation is performed. The above-mentioned problem is solved by manufacturing a single crystal under the specified crystal rotation and the predetermined manufacturing conditions.

Although not particularly limited, in the inventions according to the first to third aspects, the correlation is as follows: the diameter of the single crystal to be pulled is D (mm), the horizontal magnetic field strength is G (Gauss), and the crystal rotation of the single crystal is V (rpm), the distribution characteristics of the oxygen concentration at the outer periphery of the wafer are defined by the equation δ = aD + bG + cV + d, where δ (10 ¹⁷ atoms / cm ³ ) and a, b, c, d are constants, It is desirable to obtain constants a, b, c, and d.

According to the invention of the first aspect, the correlation obtained by adding the diameter of the single crystal to be pulled to the horizontal magnetic field strength, the crystal rotation of the single crystal, and the distribution characteristics of the oxygen concentration at the outer periphery of the wafer in advance is obtained. When manufacturing a crystal, the minimum value of the single crystal to be pulled is determined from the correlation between the limit value of the oxygen concentration distribution characteristic at the outer periphery of the wafer, the limit value of the horizontal magnetic field strength, the limit value of the crystal rotation of the single crystal, and the correlation. Find the diameter. As a result, the diameter of the single crystal to be pulled is minimized, so that the production cost of the silicon single crystal can be minimized. Further, since the distribution characteristic of the oxygen concentration at the outer peripheral portion of the wafer maintains the limit value, the oxygen concentration in the wafer surface can be made uniform.

According to the invention according to the second aspect, the correlation obtained by adding the diameter of the single crystal to be pulled to the horizontal magnetic field strength, the crystal rotation of the single crystal, and the distribution characteristics of the oxygen concentration in the outer periphery of the wafer in advance is obtained. When manufacturing a single crystal, the application is based on the correlation between the limit value of the oxygen concentration distribution characteristic at the outer periphery of the wafer, the limit value of the diameter of the single crystal to be pulled up, the limit value of the crystal rotation of the single crystal, and the correlation. Find the horizontal magnetic field strength to be used. As a result, the diameter of the single crystal to be pulled is minimized, so that the production cost of the silicon single crystal can be minimized. Further, since the distribution characteristic of the oxygen concentration at the outer peripheral portion of the wafer maintains the limit value, the oxygen concentration in the wafer surface can be made uniform.

According to the invention of the third aspect, the correlation obtained by adding the diameter of the single crystal to be pulled to the horizontal magnetic field strength, the crystal rotation of the single crystal, and the distribution characteristics of the oxygen concentration at the outer periphery of the wafer in advance is obtained. When manufacturing a single crystal, the relationship between the limit value of the distribution characteristics of oxygen concentration at the outer periphery of the wafer, the limit value of the diameter of the single crystal to be pulled up, the limit value of the horizontal magnetic field strength, and the correlation Obtain crystal rotation. As a result, the diameter of the single crystal to be pulled is minimized, so that the production cost of the silicon single crystal can be minimized. Further, since the distribution characteristic of the oxygen concentration at the outer peripheral portion of the wafer maintains the limit value, the oxygen concentration in the wafer surface can be made uniform.

It is sectional drawing which shows an example of the manufacturing apparatus with which the manufacturing method of the silicon single crystal of this invention is applied. It is a graph which shows an example of the relationship between the horizontal magnetic field intensity of the manufacturing apparatus shown in FIG. 1, and the distribution characteristic of the oxygen concentration in a wafer outer peripheral part. 2 is a graph illustrating an example of a relationship between crystal rotation of a single crystal of the manufacturing apparatus illustrated in FIG. 1 and oxygen concentration distribution characteristics in a wafer outer peripheral portion. It is a graph which shows an example of the relationship between the position of the diameter direction of the wafer of the silicon single crystal manufactured with the manufacturing apparatus shown in FIG. 1, and oxygen concentration. 2 is a graph showing an example of the relationship between the diameter of a single crystal pulled by the manufacturing apparatus shown in FIG. 1 and the distribution characteristics of oxygen concentration in the outer periphery of the wafer.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of a manufacturing apparatus to which a silicon single crystal manufacturing method according to an embodiment of the present invention is applied. A silicon single crystal manufacturing apparatus 1 (hereinafter also simply referred to as manufacturing apparatus 1) to which the manufacturing method of the present embodiment is applied includes a cylindrical first chamber 11 and a cylindrical second chamber 12, These are airtightly connected.

Inside the first chamber 11, a quartz crucible 21 containing the silicon melt M and a graphite crucible 22 protecting the quartz crucible 21 are supported by a support shaft 23 and driven. The mechanism 24 can be rotated and lifted. Further, an annular heater 25 and an annular heat insulating cylinder 26 made of a heat insulating material are disposed so as to surround the quartz crucible 21 and the graphite crucible 22. A heater may be added below the crucible 21.

A cylindrical heat shielding member 27 is provided inside the first chamber 11 and above the quartz crucible 21. The heat shielding member 27 is made of a counter metal such as molybdenum or tungsten or carbon, blocks radiation from the silicon melt M to the silicon single crystal C, and rectifies the gas flowing in the first chamber 11. The heat shielding member 27 is fixed to the heat retaining cylinder 26 using a bracket 28. A heat shield part is provided at the lower end of the heat shield member 27 so as to face the entire surface of the silicon melt M, so that radiation from the surface of the silicon melt M is cut and the surface of the silicon melt M is kept warm. May be.

The second chamber 12 connected to the upper part of the first chamber 11 is a chamber for accommodating the grown silicon single crystal C and taking it out. A pulling mechanism 32 for pulling up the silicon single crystal while rotating it with the wire 31 is provided in the upper part of the second chamber 12. A seed crystal S is mounted on the chuck at the lower end of the wire 31 suspended from the pulling mechanism 32. An inert gas such as argon gas is introduced from a gas inlet 13 provided in the upper portion of the first chamber 11. This inert gas passes between the silicon single crystal C being pulled and the heat shielding member 27, then passes between the lower end of the heat shielding member 27 and the melt surface of the silicon melt M, and further quartz. After rising to the upper end of the made crucible 21, it is discharged from the gas discharge port 14.

A magnetic field generator 41 that applies a magnetic field to the melt M in the quartz crucible 21 is disposed outside the first chamber 11 (made of a nonmagnetic shield material) so as to surround the first chamber 11. The magnetic field generator 41 generates a horizontal magnetic field toward the quartz crucible 21 and is constituted by an electromagnetic coil. The magnetic field generator 41 controls the thermal convection generated in the melt M in the quartz crucible 21, thereby stabilizing the crystal growth and suppressing micro variations in the impurity distribution in the crystal growth direction. In particular, when producing a large-diameter silicon single crystal, the effect is great. The magnetic field strength shown below is a value measured at the center position of the surface of the melt M in the quartz crucible 21.

In order to grow a silicon single crystal by the CZ method using the production apparatus 1 of the present embodiment, first, a quartz crucible 21 is filled with polycrystalline silicon and a silicon raw material to which a dopant is added if necessary. Then, the heater 25 is turned on and the silicon raw material is melted in the quartz crucible 21 to obtain a silicon melt M. Subsequently, the magnetic field generator 41 is turned on and the application of the horizontal magnetic field to the quartz crucible 21 is started, and the temperature of the silicon melt M is raised to the starting temperature. When the temperature and the magnetic field strength of the silicon melt M are stabilized, the quartz crucible 21 is rotated at a predetermined speed by the drive mechanism 24 while introducing an inert gas from the gas inlet 13 and discharging from the gas outlet 14, and the wire The seed crystal S attached to 31 is immersed in the silicon melt M. Then, the wire 31 is also gently pulled up while rotating at a predetermined speed to form a seed stop, and then the diameter is increased to a desired diameter, and a silicon single crystal C having a substantially cylindrical straight body is grown.

As the silicon single crystal C is pulled up, the liquid level of the silicon melt M in the quartz crucible 21 falls, and the conditions of the hot zone change including the application of a horizontal magnetic field from the magnetic field generator 41 to the quartz crucible 21. . In order to suppress this fluctuation of the liquid level, the vertical height of the liquid level of the silicon melt M during the pulling of the silicon single crystal C is controlled by the drive mechanism 24 to be constant. The drive mechanism 24 is controlled, for example, by the position of the crucible 21, the position of the silicon melt M measured by a CCD camera or the like, the pulling length of the silicon single crystal C, the temperature in the first chamber 11, the silicon melt This is executed according to information such as the surface temperature of the liquid M, the flow rate of the inert gas, and the like, whereby the vertical position of the quartz crucible 21 is moved by the drive mechanism 24.

For example, when manufacturing a 300 mm wafer, the pulling diameter of the silicon single crystal C is set to a predetermined value slightly larger than 300 mm in consideration of variation. FIG. 4 is a graph showing an example of distribution characteristics of oxygen concentration in the wafer state of the silicon single crystal C thus manufactured. The horizontal axis indicates the position in the diameter direction where the wafer center is 0, and the vertical axis indicates the oxygen concentration (× 10 ¹⁷ atoms / cm ³ ). The oxygen concentration referred to in this specification is a value measured by the FT-IR method (Fourier transform infrared spectrophotometry) standardized by ASTM F-121 (1979). Further, the wafer outer peripheral portion referred to in this specification is a region from the outer peripheral end portion of the wafer to the inside of 10 mm. In the following example, as a drop in the oxygen concentration at the outer peripheral portion of the wafer, an example of 5 mm from the outer peripheral end portion is shown in FIGS. 2, 3, and 5. The position is not limited to 5 mm. According to this example, the oxygen concentration in the outer peripheral portion of the wafer is lower by about 0.5 × 10 ¹⁷ atoms / cm ³ than other parts. As the diameter of the wafer is increased, a horizontal magnetic field is applied to control the thermal convection generated in the silicon melt M in the quartz crucible 21, thereby improving the pull-up diameter controllability. This is because the melt of the surface layer in which oxygen is evaporated is taken into the outer periphery of the crystal and the oxygen concentration in the outer periphery of the crystal is likely to decrease.

Therefore, if the horizontal magnetic field strength by the magnetic field generator 41 is lowered, the decrease in oxygen concentration at the outer periphery of the wafer can be suppressed. However, when the horizontal magnetic field strength by the magnetic field generator 41 is lowered, the controllability of the heat convection generated in the silicon melt M in the quartz crucible 21 is lowered, so that the pulling rate controllability is lowered. Further, when the horizontal magnetic field strength by the magnetic field generator 41 is lowered, the controllability of the heat convection generated in the silicon melt M in the quartz crucible 21 is lowered, so that the oxygen concentration is raised. Therefore, there is a certain limit value for reducing the horizontal magnetic field strength.

In addition, the crystal rotation speed of the silicon single crystal C at the time of pulling up (refers to the rotation speed of the silicon single crystal C using only the wire 31 and not the relative rotation speed considering the rotation speed of the quartz crucible 21). If it does so, the fall of the oxygen concentration in the outer peripheral part of a wafer can be suppressed. However, when the crystal rotation speed of the silicon single crystal C at the time of pulling is increased, the silicon single crystal C is twisted. Further, when the crystal rotation speed of the silicon single crystal C at the time of pulling is increased, the oxygen concentration increases. Therefore, there is a certain limit value for increasing the crystal rotation speed of the silicon single crystal C when it is pulled up.

The diameter of the silicon single crystal C to be pulled up is set to a minimum value in consideration of the diameter variation due to the control variation such as the pulling speed. However, if this diameter is increased, the amount to be discarded increases. Manufacturing yield decreases. There is also a restriction on the size of the quartz crucible 21 of the manufacturing apparatus 1. Therefore, there is a certain limit value for increasing the diameter of the silicon single crystal C when it is pulled up.

Therefore, the present inventors have determined the correlation between how the horizontal magnetic field strength, the crystal rotation speed and the diameter of the silicon single crystal C each affect the oxygen concentration distribution characteristics of the outer periphery of the crystal. Verified.

FIG. 2 shows an example of the relationship between the horizontal magnetic field strength and the distribution characteristics of the oxygen concentration at the outer periphery of the wafer when the silicon single crystal C is manufactured under predetermined conditions using the predetermined manufacturing apparatus 1 shown in FIG. It is a graph to show. The horizontal axis indicates the horizontal magnetic field strength (Gauss, G, the right side is large and the left side is small) by the magnetic field generator 41, and the vertical axis is a position (hereinafter referred to as 5 mm) from the outer peripheral edge of the wafer toward the center. (Also referred to as In5) and a difference in oxygen concentration (Oi [In10] −Oi [In5], 10 ¹⁷ atoms / cm ³ ) at 100 mm from the outer peripheral edge of the wafer toward the center (hereinafter also referred to as In10). ). As described above, it can be understood that if the horizontal magnetic field strength is lowered, the difference in oxygen concentration approaches zero.

FIG. 3 shows the crystal rotation speed of the single crystal (referred to the rotation speed of the single crystal C itself) and the outer periphery of the wafer when the silicon single crystal C is manufactured using the manufacturing apparatus 1 shown in FIG. It is a graph of an example of the relationship with the distribution characteristic of oxygen concentration in. The horizontal axis represents the crystal rotation speed of the single crystal (rpm, the right side is large and the left side is small), and the vertical axis is the difference in oxygen concentration (Oi [In10] −Oi [In5], 10 ¹⁷ atoms / cm ³ ). As described above, it can be seen that the oxygen concentration difference approaches zero when the crystal rotation speed is increased.

FIG. 4 is a graph showing an example of oxygen concentration distribution characteristics in the wafer state of the silicon single crystal C when a 300 mm wafer is manufactured as described above. FIG. 5 uses the results shown in FIG. 4 and assumes that the distribution characteristics (oxygen behavior) of the oxygen concentration at the outer periphery of the pulled diameter do not change regardless of the diameter. This is a guessed graph. The horizontal axis shows the diameter of the single crystal set when pulling up (mm, the right side is large and the left side is small), and the vertical axis is the difference in oxygen concentration (Oi [In10]) as in FIGS. -Oi [In5], 10 ¹⁷ atoms / cm ³ ). As described above, it can be seen that the difference in oxygen concentration approaches zero if the diameter of the single crystal when pulling is set large.

2 to 5, the oxygen concentration distribution characteristics (Oi [In10] −Oi [In5], 10 ¹⁷ atoms / cm ³ ) at the outer periphery of the crystal are obtained from the horizontal magnetic field strength and the rotational speed of the silicon single crystal C. And the diameter of the single crystal when pulled up is D (mm), the strength of the horizontal magnetic field is G (Gauss), and the crystal of the single crystal when pulled up When the rotational speed is V (rpm), the oxygen concentration distribution characteristic at the outer periphery of the wafer is δ (10 ¹⁷ atoms / cm ³ ), and a, b, c, d are constants,
[Equation 1]
δ = aD + bG + cV + d (Formula 1)
The correlation was defined by the following formula. The constants a, b, c, and d correspond to weights for the horizontal magnetic field strength, the rotational speed and the diameter of the silicon single crystal, respectively.

Then, constants a, b, c, and d are obtained in advance under predetermined manufacturing conditions for each silicon single crystal manufacturing apparatus 1, and the limit value (allowable value) of the oxygen concentration distribution characteristic δ at the outer periphery of the wafer is obtained. ), The limit value of the horizontal magnetic field strength, and the limit value of the crystal rotation speed of the single crystal at the time of pulling up are substituted into the above equation 1, and the silicon single crystal diameter D (= (δ−bG−cV) obtained by this is substituted. -D) / a) is set to the diameter of the silicon single crystal C to be pulled up.

Here, the limit value (allowable value) of the oxygen concentration distribution characteristic δ at the outer peripheral portion of the wafer is the maximum value of the distribution value (sag value) of the outer peripheral oxygen concentration allowed for the wafer as a product. The product shipment standard set according to the above. For example, Oi [In10] −Oi [In5] = 0.5 × 10 ¹⁷ atoms / cm ³ . Further, the limit value of the horizontal magnetic field strength is a lower limit value in consideration of the controllability of the pulling rate and the increase in oxygen concentration as described above, and the manufacturing conditions for each silicon single crystal manufacturing apparatus 1 based on experience values and simulations. It is determined every time. For example, it is 2000G, 3000G or 4000G. Moreover, the limit value of the crystal rotation speed of the single crystal at the time of pulling is an upper limit value in consideration of an increase in the bend and oxygen concentration, and is determined for each manufacturing condition for each manufacturing apparatus 1 based on experience values and simulations. For example, 8 rpm, 9 rpm, 10 rpm, 12 rpm, or 15 rpm.

An example of constants a, b, c, and d in Equation 1 was obtained by regression analysis of the examples shown in FIGS. 2 to 5 and was as follows.
[Equation 2]
δ = −0.0166D + 0.0005G−0.4836V + 8.11984 (Formula 2)

In the above formula 2, the limit value (allowable value) of the distribution characteristic δ of the oxygen concentration at the outer periphery of the wafer is 0.1 × 10 ¹⁷ atoms / cm ³ , the limit value of the horizontal magnetic field strength is 2500 G, and a single crystal crystal when pulling up When the limit value of the rotation speed is set to 8 rpm and is substituted into the above equation 2, the diameter D of the silicon single crystal obtained by this is 330 mm. If a silicon single crystal is manufactured with this diameter D as a set value, the distribution characteristic δ of the oxygen concentration at the outer periphery of the wafer is satisfied to be 0.5 × 10 ¹⁷ atoms / cm ³ or less, and the controllability of the pulling rate is high. It is possible to obtain an ingot that is good, suppresses an increase in oxygen concentration and bends, and further minimizes the amount of the outer peripheral portion discarded when processing into a wafer having a specified diameter.

In the above-described example, the limit value of the distribution characteristic δ of the oxygen concentration at the outer periphery of the wafer, the limit value of the horizontal magnetic field strength, and the limit value of the crystal rotation speed of the single crystal at the time of pulling are substituted into Equation 2, thereby Although the diameter D of the single crystal was obtained, instead of this, the limit value of the oxygen concentration distribution characteristic δ at the outer periphery of the wafer, the limit value of the diameter of the silicon single crystal, and the crystal rotation of the single crystal at the time of pulling up A silicon single crystal may be manufactured by substituting the limit value of the velocity, thereby obtaining the horizontal magnetic field strength, and setting the obtained horizontal magnetic field strength. In place of this, the limit value of the distribution characteristic δ of the oxygen concentration at the outer periphery of the wafer, the limit value of the diameter of the silicon single crystal, and the limit value of the horizontal magnetic field strength are substituted into Equation 2, and the single crystal when pulling up by this is substituted. A single crystal of silicon may be manufactured by obtaining the crystal rotation speed of the first and setting the obtained crystal rotation speed.

DESCRIPTION OF SYMBOLS 1 ... Manufacturing apparatus of a silicon single crystal 11 ... 1st chamber 12 ... 2nd chamber 13 ... Gas inlet 14 ... Gas outlet 21 ... Quartz crucible 22 ... Graphite crucible 23 ... Support shaft 24 ... Drive mechanism 25 ... Heater 26 ... Insulating cylinder 27 ... Heat shielding member 28 ... Bracket 31 ... Wire 32 ... Pulling mechanism 41 ... Magnetic field generator M ... Silicon melt C ... Silicon single crystal S ... Seed crystal

Claims

The correlation between the diameter of the single crystal when pulled by the CZ method, the horizontal magnetic field strength applied to the melt, the crystal rotation speed of the single crystal when pulled, and the distribution characteristics of the oxygen concentration at the outer periphery of the wafer are predetermined. Obtain in advance about the manufacturing conditions of
From the limit value of the oxygen concentration distribution characteristic at the outer periphery of the wafer, the limit value of the horizontal magnetic field strength, the limit value of the crystal rotation speed of the single crystal at the time of pulling up, and the correlation, the single crystal at the time of pulling up Find the smallest diameter of
A method for producing a silicon single crystal, wherein a silicon single crystal is produced under the predetermined production conditions using the determined minimum diameter as a target diameter.
The correlation between the diameter of the single crystal when pulled by the CZ method, the horizontal magnetic field strength applied to the melt, the crystal rotation speed of the single crystal when pulled, and the distribution characteristics of the oxygen concentration at the outer periphery of the wafer are predetermined. Obtain in advance about the manufacturing conditions of
Applied from the limit value of the distribution characteristic of the oxygen concentration in the outer periphery of the wafer, the limit value of the diameter of the single crystal when the pulling, the limit value of the crystal rotation speed of the single crystal when the pulling, and the correlation Find the horizontal magnetic field strength to
A method for producing a silicon single crystal, wherein a single crystal is produced under the obtained horizontal magnetic field strength and the predetermined production conditions.
The correlation between the diameter of the single crystal when pulled by the CZ method, the horizontal magnetic field strength applied to the melt, the crystal rotation speed of the single crystal when pulled, and the distribution characteristics of the oxygen concentration at the outer periphery of the wafer are predetermined. Obtain in advance about the manufacturing conditions of
From the limit value of the distribution characteristic of the oxygen concentration in the outer periphery of the wafer, the limit value of the diameter of the single crystal at the time of pulling up, the limit value of the horizontal magnetic field strength, and the correlation, the single crystal at the time of pulling up Find the crystal rotation speed,
A method for producing a silicon single crystal, comprising producing a single crystal under the determined crystal rotation speed and the predetermined production conditions.
The diameter of the single crystal at the time of pulling is D (mm), the horizontal magnetic field strength is G (Gauss), the crystal rotation speed of the single crystal at the time of pulling is V (rpm), and the distribution characteristics of oxygen concentration at the outer periphery of the wafer. When δ (10 17 atoms / cm 3 ), a, b, c, and d are constants, the correlation is defined by the following equation: δ = aD + bG + cV + d, and the constants a, The method for producing a silicon single crystal according to any one of claims 1 to 3, wherein b, c and d are obtained.